Semiconductor elements are becoming more and more versatile and have been miniaturized in the extreme. Integrated circuits have become packed with elements and functions. With these advances, the elements are generating more and more heat due to the density and high speed of the operations. It is not unusual now to encounter thermal energy in the amount of 10 watts per square centimeter and this is expected to increase further in the future.
The heat generation is further aggravated by the density of elements mounted within a confined area. There is a need for simple and efficient heat sink configurations which can be easily manufactured. It is a purpose of this invention to create a heat sink element shaped to provide an air flow around, and a conduction path through the element which will accelerate the conduction of heat away from the semiconductor element.
As shown in FIG. 1 of U.S. Pat. No. 5,763,950, the heat sink of the prior art comprises a base 11a which is in direct contact with a surface of the semiconductor. A series of cylindrical pins 14 are mounted on the base 11a and extend perpendicular to the base. The pins form a matrix of passages through which cooling air can flow and dissipate heat conducted to the pins by convection. In addition, the pins 14 will conduct heat away from the base 11a because of the temperature differential between the base and ambient air. The material will perform in accordance with its Coefficient of Thermoconductivity and is selected accordingly. In the past improvements were sought in the efficiency of heat extraction through the construction of extended surface areas such as fins on the pins. The fins could be longitudinally extending or transverse to the axis of the pin. The sole purpose of these designs was to create more surface area over which the ambient air may flow by convection. In addition, as in the case of the '950 patent, a supplemental air flow is injected to augment convection.